Ecology Xochimilco The Struggle for Surviva l1 Iván Trujillo* exico City. Streets and houses as The arrival of the Spaniards and the estab - far as the eye can see. Looking at lishment of colonial power changed the look of the enormous asphalt and concrete M the city, as did different hydraulic works down mass, it is hard to believe that Greater through the years. Through it all, however, the Tenochtitlan was built on a lake and that the lake continued to be an important resource. power and splendor of the Aztec empire was At the end of the nineteenth century, the due in great part to its inhabitants’ efficient city still had a wide network of canals through use and management of water. on which canoes and other vessels circulated transporting agricultural products to market. It * Biologist. Director of the UNAM Film Archive. is not surprising that these canals were one of a í u g n u M l e i n a D y b s o t o h P Xochimilco Ecological Park. Voices of Mexico • 53 the things that most attracted the attention ria . The borticella do not move, but their crowns of the men the Lumière brothers sent to shoot of cilia create whirlpools that act like tiny vac - the first film ever in Mexico 100 years ago. uum cleaners, pulling the food in. Today, several centuries after the conquest, it Protozoans are in turn the main food of larg - is still possible to catch a glimpse of what life was er animals such as the nematodes, or round - like in pre-Hispanic Mexico when you go to one of worms, constantly seeking prey. But, in terms of Mexico City’s surviving lake regions, Xochimilco. voracity, it is the insect and crustacean larva that Considered by many a picturesque tourist are the best examples of how to eliminate every - attrac tion, Xochimilco lake offers much more thing that crosses their path; the pitched battles than that and has resisted more or less suc - among them for food are truly surprising. cessfully being absorbed by the metropolitan Here in Xochimilco also lives a kind of fresh area. Cer tainly, Xochimilco is not what it used water shrimp, the acocil , as our ancestors called it, to be, but its 187 kilometers of canals still hold surprises for us. AN UNDERWATER UNIVERSE Its origins are in the water. The apparent calm on the surface of the canals and lakes con trasts sharply with the struggle for survival under the surface. Thanks to chlorophyll, the algae and water plant cells get the energy they need from the sun to produce nutritious substances that a veritable universe of microorganisms depend on to live. Untiringly, the ciliata absorb and expel water from which they obtain bacilli and other bac te - Xochimilco Ecological Park. Xochimilco, an endangered paradise, has resisted more or less successfully being absorbed by the city. 100 Ecology which has a voracious appetite as well. Con si d - man der group. However, adult salamanders er ed a parasite that feeds on carrion, it is fussy not devel op lungs, leave the water and return only only about eating, but also about mating, which can to lay their eggs. The axolotl lives all its life in take several hours. Most of its young will be food the water, breathing through its elegant collar for other larvae. However, some will survive and of gills. live to reproductive age, and so begin the cycle This behavior, called neoteny, caused con - again. But even in old age, they cannot be assured fusion and led people to think the axolotl was of peace, because the acocil is the favo ri te deli - not a salamander at all until in 1865 when a cacy of a singular inhabitant of the waters of Xo - few held in captivity in France went through chimilco, the axolotl, a kind of larval salamander. their complete metamorphosis. Later, José Ma - The axolotl (from the Nahuatl word for ría Ve lasco continued his observations based “water monster”) is an amphibian of the sala - on the work of the French, describing how during draughts, the axolotl developed lungs and behaved like genuine salamanders. He accompanied his findings with magnificent sketches. But no one can describe the axolotl like Julio Cortázar did. An inexpressive face, with no feature other than the eyes, two orifices like pinheads of transpar - ent gold, totally lifeless, but watchful, letting me penetrate it with my gaze, that seem to go beyond the golden point and lose itself in a diaphanous interior mystery. It was its calm that first fascinated me about the axolotl. I felt darkly that I shared its secret will, that I eliminated space and time with indifferent Flower garden. Xochimilco Ecological Park. The apparent calm on the surface of the canals and lakes contrasts with the struggle for survival underneath. 101 Voices of Mexico • 53 The water lily, introduced in the early twentieth century, became a blight, constantly choking up the canals. immobility. Later I learned to know better; the Our ancestors contraction of their gills, their tiny legs feeling thought up an ingenious their way along the rocks, their suddenly swim - ming off. All this proved to me that they were able agricultural system that provided to come out of that mineral-like lethargy in which them with a constant supply they spend hours at a time. 2 of food: the chinampas , artificial agricultural Axolotls’ reproduction is not easy to observe. islands. Apparently, the male deposits his sperm on the bottom and the female immerses herself in it to fertilize the eggs. Afterwards, she deposits them one by one among the vegetation. Slowly, the young develop in capsules until they emerge, ORIGINS looking very like the adults, to continue their growth outside. Using the resources they had at hand, our Another peculiarity of the axolotl is its enor - ancestors thought up an ingenious agricultural mous powers of regeneration: it is capable of system that provided them with a constant producing a new member if it loses one. But supply of food: the chinampas . no regeneration is possible when it comes up Chinampas are artificial agricultural islands against the water snakes so common in Xo - where water is literally a stone’s throw away. chi milco and one of whose favorite foods is The “fields” are fertilized with mud rich in axolotl. nutrients dug up from the bottom of the lake. In addition to the snakes that come to the Today pre-Hispanic practices are still used in surface, the banks of the canals boast an enor - the care and maintenance of the chinampa . mous number of insects that need the lake Originally, a chinampa was begun after find - either for laying their eggs or for food. The most ing a shallow place in the lake where lots of silt surprising thing about all this is that the banks and mud were deposited. A thick layer of rush - of the canals are man-made. es, reeds and other grasses were put there, on 102 Ecology The axolotl, a legendary inhabitant of the canals. Pre-Hispanic techniques are still used in the care and maintenance of the chinampa . animal protein. In the markets of Xochimilco The ahuejote ’s you can still buy acocil , frogs and axolotl pre - deep, wide roots form pared in different ways, and they continue to a mesh that keeps the chinampa in be a favorite dish of many locals. place, preventing its moving or disintegrating. It also protects AN ENDANGERED PARADISE crops from strong winds and hail. But problems came to this paradise, too. The city’s excessive growth depleted the under - ground springs that fed Xochimilco. Streets and avenues made their appearance and now the tall top of which more soil was placed. Later, rows of ahuejotes guard sidewalks as the only testimony ahuejote , willow trees native to Mexico, were that in the past they had surroun ded chinampas . planted around it to fix it. The ahuejote ’s deep, The water lily, introduced in the early twen - wide roots formed a mesh that kept the chinam - tieth century, became a blight, constantly dry - pa in one place, preventing its moving or disin - ing up the canals. Rodents proliferated in the tegrating. Its vertical branches did not make much fields; the proof is the abundance of rattles na kes shade, but did protect crops from strong winds that feed on them. and hail. In addition, the wood of the ahuejote By the end of the last century, the lake was is resistant to humidity and therefore was used in danger of completely drying up. However, to make different tools for cultivation. The small, after prompting by local inhabitants, proud of tender branches were used to make baskets, and their past and traditions, the UNESCO declared its young buds had medicinal uses , given their Xo chimilco a World Heritage Treasure in 1987, analgesic properties similar to those of aspirin. and the Eco logical Recovery of Xochi milco pro - Thus, the lake not only guaranteed its in - ject began. habitants the security of a good crop, 3 but its Today, the lake’s water is treated and returned native fauna was also a permanent source of free of contaminants; a tireless struggle against 103 Voices of Mexico • 53 name from us: Xochimilco, from the Nahuatl words for flower, xochitl , and cultivated land, mili . Although flowers are brought in from else - where for sale, the chinampas continue the tra - dition of producing different varieties for sale in Xochimilco’s many markets. Probably no other place in the world offers the buyer the quantity and variety of flowering plants sold here.